Sliding lift door



March 31, 1942. F. DrrcHFlELD f 2,278,065

SLIDING LIFT DOOR l Filed Dec. 2, 1938 2 Sheets-Sheet 1 I hva/5N Tae FRG/W( D/ TCHF/HD Patented Mar. 31, 1942 SLIDING LIFT DOOR Frank Ditchfield, Cleveland,` Ohio, assignor to The Youngstown Steel Dooi Company, Cleveland, Ohio, a corporation of Ohio Application December 2, 1938, Serial No. 243,590

1 Claim.

This invention relates to sliding lift doors and more specifically to lift mechanisms for said doors.

It is an object of this invention tol provide lift mechanisms for lsliding doors in which wear between the elements of said mechanisms shall be substantially reduced to the end that the initial lift obtainable by said mechanisms shall not be materially affected. v

A further object is to provide lift mechanisms for sliding doors so constructed that concentration of Wear upon relatively .small areas of said mechanisms is obviated and distribution of such wear over substantial areas is secured whereby the amount of lift obtainable is substantially unaiected.

Other objects of the invention will become clear as the description thereof proceeds.

In the drawings forming part of this specification:

Figure 1 is an elevation showing a sliding car door having a lift mechanism embodying the instant invention.

Figure 2 is yan enlarged elevation of a portion of the lift mechanism.

Figure 3 is a vertical section taken on line 2-2 of Figure 1.

Figure 4 is a horizontal section taken on line 3-3 of Figure 1.

Figure 5 is a horizontal section taken on line 4--4 of Figure l.

Referring to the drawings, a lift mechanism embodying the instant invention is illustrated applied to a sliding door I of a railway box car. The door l0 is selected for purposes of illustration only and as shown is of metallic construction. The door embodies a metallic panel formed with a plurality of spaced horizontal corrugations l2 and marginal vertical corrugations I3 and I4 into which the horizontal corrugations merge.

The marginal portions of the door are reinforced, the reinforcement for the upper margin being in the form of an angle I secured upon the outside of the metallic panel I I and arranged so that one of its legs I6 extends horizontally inwardly, as is clearly shown in Figure 3 of the drawings. The reinforcement for the front Vertical margin of the door is a substantially channel shaped member I1 while the rear'vertical margin of the door is reinforced by means of a door sealing strip I8 and a buffer angle I9. The lower horizontal margin of the door is reinforced by means of an angle member 20.

As clearly appears from Figure 1 of the drawings, the door is supported upon an angle track member 2| arranged with one ange 22 extending horizontally and the remaining flange 23 vertically downwardly. The track 2| is supported by means of a pluralityof track brackets 24 carried by the underframe of the box car which is designated generally by thev reference numeral 25.

When the door is in its normal or lowered position, it is seated irictionally upon the track 2|.

Frictional engagement of the door with the track is established through the bottom door reinforcing angle member 20 as clearly appears in Figure 2 of the drawings. For movement vof the door between open and closed positions lift mechanism is provided whereby the door is elevated so as to break thefrctional engagement thereof with the track and supported upon antifriction means for ready movement upon the track.

As illustrated, the lift mechanism embodies the spaced housing members 23 within each of which is disposed a roller 21. Each roller is in the form of an eccentric and includes a core member 28 :and a rim member 29. Between these members there is interposed a roller bearing 3D. The rim member of each of the rollers, as clearly appears from Figures 1 and 2 of the drawings, engages the track 2|.

A pin or axle 3| extends eccentrically through each core member 28 and is journalled in the housing member. Each of the pins or `axles 3| carries an arm 32 provided with a lug 33. The lugs 33 project through openings provided in the flattened ends 34 of a bar 35 so that uniform lifting of the door is secured.

For the purpose of actuating the lift mechanism and elevating the door a lever 3B is provided, the lever being preferably mounted upon one end of a pin 3| and being guided in its movement by the overlapping cooperation between a substantially Z-shaped clip 31 carried by the lever and an arcuate flange 38 formed on the housing member.

The pins 3| utilized in the instant invention are formed with a multiplicity of having faces 39. The core members 28v of the rollers 2T are formed with a corresponding multiplicity of internal bearing faces 40 which engage the .bearing faces formed in the pins 3|. Similarly, the lever 36 is provided with internal bearing faces as indicated at 4|, these faces also engaging the bearing faces formedy on one of the pins 3| with which the lever is slidably engaged. Where bushings such as 42 and 43 are employed as is preferable they are provided with internal bearing faces engaging the faces formed in the pins 3l. This construction, moreover, is carried into the arms 32 mounted upon the pins. It is to be observed that the bushings 42 and 43 are received Within the bearings 44 and 45 formed in the housing members as is more clearly shown in Figures 3 and 4 of the drawings.

The pins are slidably engaged with the several elements of the lift mechanism enumerated above. Hence the pins are formed with shoulders 4B disposed in overlapping relationship to the .bushings 42 whereby accidental disengagement of the pins from the several elements of the lift mechanism by inward sliding of the pinsv is avoided. Sliding and disengaging movement of the pins in the opposite direction is prevented by the expedient of peening over the inner ends of the pins upon the bushings 43 as shown at.41 in Figures 3 and 4 of the drawings.

A portion of the door opposite each pin is removed as indicated at 48 so that pins of sufcient length to provide material-for the peening operation mai7 be utilized.

Prior to applicants invention bearing of the operating lever upon the pin on which it was mounted and bearing of the pins upon the roller cores were limited to very small areas. The forces incident upon these lmembers were therefore concentrated, thereby setting up severe wear in these small areas. As a consequence it was found that the amount of lift of the door'initially obtainable by the lift mechanism is seriously reduced. By the described invention, however, this highly undesirable condition is precluded. Concentration of stresses and resulting wear are avoided and a substantially uniform distribution of these stresses upon the co-acting bearing faces of the several members mounted upon the pin is secured. Substantial maintenance of the full lifting eiect of the mechanism is thereby insured and expensive repairs eliminated.

It will be apparent that numerous changes and modifications in the details of the invention will be clear to those skilled in the art. It is intended, therefore, that all such modifications and changes be comprehended within this invention, which is to be limited only by the scope of the claim appended hereto.

I claim:

Lift mechanism for a sliding car door embodying-a plurality of roller housings, each provided with a roller having a core and a relatively rotatable rim and a pin extending eccentrically through said core and journalled in said housing, said pin being rotatable with said core and an operating lever slidably mounted on one of said pins, each pin being assembled by insertion from the outside of a housing and having a shoulder on the outer portion thereof to limit said insertion, the inner ends of said pins being peened over to prevent disengagement from said housing, a plurality of bearing faces formed substantially around the periphery of the one pin, a plurality of corresponding internal bearing faces formed on said lever, said lever being subjected to a whipping action during transit of said car, said bearing faces on said lever engaging the bearing faces on said one pin whereby the pressure between said lever and said one pin set up by the whipping action of said lever is distributed over a large area, said lever being removable and selectively re-engageable with said pin to re-establish engagement between said bearing faces in order to compensate for wear which might occur.

FRANK DITCHFIELD. 

